Electronic equipment, PCB assembly and preparation method thereof

Abstract

The invention provides electronic equipment, a PCB assembly and a preparation method of the PCB assembly. The preparation method comprises the following steps: respectively forming via holes in at least two PCBs; arranging the shock insulator provided with the connecting through hole between the adjacent PCBs and respectively connecting the shock insulator with the adjacent PCBs; wherein the connecting through hole of the spacer is arranged corresponding to the via hole on the adjacent PCB; and liquid is poured into the accommodating holes jointly formed by the connecting through holes of the shock insulators and the via holes of the PCBs, and is solidified to fill the accommodating holes, so that the plurality of PCBs are fixedly connected. According to the preparation method of the PCB assembly provided by the embodiment of the invention, the adjacent PCBs are connected by using the shock insulator with the hole, and then the liquid is poured into the accommodating hole and is solidified to fill the accommodating hole, so that the fixed connection of the plurality of PCBs is realized, and the PCB assembly obtained by the preparation method has the characteristics of compact overall structure, high reliability and the like. The connecting piece has the characteristics of small occupied space and high connection reliability, can be applied to the electronic equipment, and facilitates the miniaturization design of the electronic equipment.

Description

Technical Field

[0001] The present application relates to the technical field of PCB board stacking structures, and in particular to an electronic device, a PCB board assembly and a preparation method thereof. Background Art

[0002] With the development of communication technology and the needs of people's daily life, terminal communication equipment integrates more and more functions. In order to achieve more functions, there are more and more electronic components in electronic equipment. This also requires the continuous increase in the available area of ​​PCB boards carrying electronic devices. But contradictory to this, people hope that terminal equipment can be made thinner and lighter, and the battery life is getting stronger and stronger. The premise of long battery life is a large-capacity battery, and large-capacity electronics means an increase in battery volume. All of the above point to a requirement, that is, a PCBA that can make full use of the internal space of the device, has as large an electronic device bearing area as possible, and as high a density as possible.

[0003] The commonly used method now is to use a multi-PCB stacking solution to extend the internal space of the terminal from a plane to a three-dimensional one. The number of times the PCB is stacked ranges from 2 to 3 times. The stacking method of the PCB is generally a sandwich structure. The so-called sandwich stacking is similar to the sandwich method, in which multiple boards are stacked together and the middle is elevated in the form of a middle frame board, so as to form a cavity in the middle of the multiple boards, and the components can be placed inside the cavity. In addition to playing a role in the process, the middle frame board also plays a role in electrical connection, that is, to connect and communicate the electrical signals between multiple PCBs. The principle is that there are many vias on the bracket board that penetrate the PCB, and the vias become a "bridge" for the signal after copper plating. After the multi-layer PCB is welded, the signal can be transmitted through this "bridge".

[0004] Although the sandwich structure is connected by pads to combine the entire PCB module together, each layer of the PCB itself is also a multi-layer structure. Figure 1 , Figure 1 This is a schematic diagram of a conventional sandwich structure PCB stack. When the soldering is good, the bonding force between the solder paste 10a and the pad 10b will be greater than the bonding force between the pad 10b and the resin glass fiber layer 10c. When the terminal falls or is impacted, the internal PCB may be deformed. At this time, the pad may fall off at the deformation point, causing the signal to open and the device to be damaged. The mark 10d in the figure indicates the connecting small board, and 10e indicates the middle circuit layer. 10z indicates the falling gap.

[0005] In order to reduce the debonding damage, the existing technology generally uses screw reinforcement. That is, in the entire sandwich structure, in the bonding pad area, screws are used to lock the entire structure at intervals. Figure 2 , Figure 2 It is a schematic diagram of the structure in which conventional sandwich structure PCB boards are stacked and reinforced by screws. The 10f marked in the figure represents the screws and 10g represents the electronic components.

[0006] The existing technology uses screws to fix the entire PCB module, which can indeed play a reinforcement role, but the space it occupies is too large. In order to ensure operability and strength, the diameter of each screw exceeds 1mm, the diameter of the PCB opening exceeds 1.5mm, and the nut is even larger, with a diameter of more than 2mm. Nuts that are too large will affect the layout of components and the design of internal circuits of the PCB, especially in some bottleneck areas, where the available area itself is very small, and after being occupied by screws, it cannot be used for layout and wiring design. This is a major pain point in the current design. On the other hand, the screws have a certain force during the tightening process, which may have a destructive effect on the periphery of the PCB, so a certain safety distance needs to be left when laying out and wiring the PCB, which also takes up some available space. Summary of the invention

[0007] A first aspect of an embodiment of the present application provides a method for preparing a PCB board assembly, the method comprising:

[0008] Forming via holes on at least two PCB boards respectively;

[0009] A spacer with connecting through holes is arranged between adjacent PCB boards and connected to the adjacent PCB boards respectively; wherein the connecting through holes of the spacer are arranged corresponding to the via holes on the adjacent PCB boards;

[0010] Liquid is poured into the receiving hole formed by the connecting through hole of the spacer and the via hole of the PCB board, and the liquid is solidified to fill the receiving hole, thereby achieving fixed connection of multiple PCB boards.

[0011] In a second aspect, an embodiment of the present application provides a PCB board assembly, and the PCB board assembly is prepared by the preparation method described in the above embodiment.

[0012] In a third aspect, an embodiment of the present application provides an electronic device, wherein the electronic device includes the PCB board assembly described in the above embodiment.

[0013] The preparation method of the PCB board assembly provided in the embodiment of the present application realizes the fixed connection of multiple PCB boards by connecting adjacent PCB boards with spacers with holes, and then pouring liquid into the receiving holes and solidifying to fill the receiving holes. The PCB board assembly obtained by the preparation method has the characteristics of compact overall structure, small space occupied by connecting parts and high connection reliability. It can be applied to electronic equipment and is conducive to the miniaturization design of electronic equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 This is a schematic diagram of a conventional sandwich structure PCB board stack;

[0016] Figure 2 This is a schematic diagram of the structure of a conventional sandwich structure PCB stack reinforced by screws;

[0017] Figure 3 It is a schematic flow chart of an embodiment of a method for preparing a PCB board assembly of the present application;

[0018] Figure 4 This is a schematic diagram of the split structure of a three-layer PCB board in the present application;

[0019] Figure 5 It is a structural schematic diagram of an embodiment of a spacer member of the present application;

[0020] Figure 6 It is a partial structural schematic diagram of an embodiment of a PCB board assembly of the present application;

[0021] Figure 7 is a schematic diagram of another connection structure in the preparation method of the present application;

[0022] Figure 8 yes Figure 7 Schematic diagram of the middle sealing ring under the action of external force;

[0023] Fig. 9 It is a partial structural schematic diagram of another embodiment of the PCB board assembly of the present application;

[0024] Fig.10 It is a structural schematic diagram of an embodiment of a PCB board assembly of the present application;

[0025] Fig.11 It is a flow chart of another embodiment of the method for preparing a PCB board assembly of the present application;

[0026] Fig.12 It is a schematic diagram of the structure of forming a bolt cap by using a jig;

[0027] Fig.13 It is a schematic diagram of the structure of forming a bolt cap by blind fishing;

[0028] Fig.14 It is a schematic diagram of the structure before the tin material fixing bolt is formed during the patch process;

[0029] Fig.15 It is a schematic diagram of the structure after the tin material fixing bolt is formed during the patch process;

[0030] Fig.16 It is a structural schematic diagram of another embodiment of the PCB board assembly of the present application;

[0031] Fig.17 It is a structural schematic diagram of another embodiment of the PCB board assembly of the present application;

[0032] Fig.18 It is a structural schematic diagram of an embodiment of the electronic device of the present application;

[0033] Fig.19 yes Fig.18 A schematic cross-sectional view of the structure of the electronic device at AA in the embodiment;

[0034] Fig. 20 It is a schematic diagram of the structural composition block diagram of an embodiment of the electronic device of the present application. DETAILED DESCRIPTION

[0035] The present application is further described in detail below in conjunction with the accompanying drawings and examples. It is particularly noted that the following examples are only used to illustrate the present application, but are not intended to limit the scope of the present application. Similarly, the following examples are only some embodiments of the present application rather than all embodiments, and all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0036] The terms "first", "second", and "third" in the embodiments of the present application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", and "third" can expressly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the embodiments of the present application, all directional indications (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. The terms "including" and "having" in the embodiments of the present application and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or components inherent to these processes, methods, products, or devices.

[0037] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] As used herein, "electronic devices" (or simply "terminals") include, but are not limited to, devices configured to receive / send communication signals via a wireline connection (e.g., via a public switched telephone network (PSTN), a digital subscriber line (DSL), a digital cable, a direct cable connection, and / or another data connection / network) and / or via a wireless interface (e.g., for a cellular network, a wireless local area network (WLAN), a digital television network such as a DVB-H network, a satellite network, an AM-FM broadcast transmitter, and / or another communication terminal). Communication terminals configured to communicate via a wireless interface may be referred to as "wireless communication terminals", "wireless terminals" or "mobile terminals". Examples of mobile terminals include, but are not limited to, satellite or cellular phones; personal communication system (PCS) terminals that may combine cellular radiotelephones with data processing, fax, and data communication capabilities; PDAs that may include radiotelephones, pagers, Internet / intranet access, web browsers, organizers, calendars, and / or global positioning system (GPS) receivers; and conventional laptop and / or palmtop receivers or other electronic devices that include radiotelephone transceivers. A mobile phone is an electronic device equipped with a cellular communication module.

[0039] The present application embodiment first provides a method for preparing a PCB board assembly. Figure 3 , Figure 3 This is a flow chart of an embodiment of a method for preparing a PCB board assembly of the present application. It should be noted that the PCB board assembly obtained by the preparation method of the present application can be used in electronic devices, and the electronic devices may include mobile phones, tablet computers, laptop computers, wearable devices, etc. The preparation method includes but is not limited to the following steps.

[0040] Step S100, forming via holes on at least two PCB boards respectively.

[0041] This embodiment is described using a three-layer PCB board as an example. Figure 4 , Figure 4 This is a schematic diagram of the split structure of a three-layer PCB board of the present application, wherein a fixed position is made on the PCB board (110, 120, 130), and a certain size of via hole 101 is designed, such as drilling a via hole 101 with a diameter of 0.5 mm. The mark 102 in the figure indicates the position of the copper leak or solder joint on the PCB board.

[0042] Please continue reading Figure 3 The preparation method in this embodiment further includes step S200, where a spacer member having connecting through holes is disposed between adjacent PCB boards and connected to the adjacent PCB boards respectively.

[0043] In this step, in one embodiment, a metal gasket of a certain size may be designed, see Figure 5 , Figure 5 It is a structural schematic diagram of an embodiment of a spacer component of the present application, wherein the spacer component 140 is a metal gasket, such as a 1mm diameter, and a connecting through hole 141 is provided in the middle of the metal gasket. The aperture of the connecting through hole 141 is slightly larger than the aperture of the via 101 on the PCB board, such as 0.6mm.

[0044] See also Figure 6 , Figure 6 It is a partial structural schematic diagram of an embodiment of a PCB board assembly of the present application, wherein a solder pad 150 is designed on the PCB board, and the metal gasket is respectively connected to the solder pad 150 on the adjacent PCB board by welding (connected through the solder layer 103), wherein the solder pad 150 is provided with an avoidance hole 151 corresponding to the via 101, and the connecting through hole 141 of the spacer, the via 101 on the adjacent PCB board and the avoidance hole 151 on the solder pad are all correspondingly arranged, and are jointly surrounded to form a receiving hole 1001 for subsequent liquid injection. Optionally, the aperture of the solder pad avoidance hole 151 is larger than the aperture of the spacer connecting through hole 141, and the aperture of the spacer connecting through hole 141 is larger than the aperture of the PCB board via 101, so as to ensure that a certain distance is left between the solder pad 150 and the via on the PCB board, and to ensure that the molten solder will not flow into the via 101 of the PCB board and block the via 101 when combined. At the same time, it is also necessary to ensure that the solder is full and there is no tin deficiency or leakage, and to ensure that there is no gap between the metal gasket and the pad.

[0045] Here, it is not necessary to use the metal gasket welding method. The purpose of the gasket here is to seal the gap between the two PCB boards to ensure that the molten liquid does not seep out of the gap. In other words, as long as the method can achieve the sealing effect, it is applicable to this solution.

[0046] Please also read Figure 7 and Figure 8 , Figure 7 is a schematic diagram of another connection structure in the preparation method of the present application, Figure 8 yes Figure 7Schematic diagram of the sealing ring under the action of external force. The connection structure (i.e., sealing structure) in this embodiment can be a sealing ring 160 made of a certain elastic material. The sealing ring 160 is connected to the adjacent PCB board through external pressure and can also play a sealing role. Optionally, the material of the sealing ring 160 is rubber or elastic resin. The connection process of the sealing ring made of elastic material with the adjacent PCB board under the action of pressure is a pre-positioned weak connection, which provides and pre-positions the receiving hole 1001 for the subsequent injection of liquid.

[0047] In addition, in one embodiment, pads may be designed at a certain distance to fill the gap with the pads themselves. The pads are not limited to circular or square shapes, as long as they can be sealed. Fig. 9 , Fig. 9 It is a partial structural schematic diagram of another embodiment of the PCB board assembly of the present application, wherein the spacer is a solder material 170 connected between adjacent PCB board pads 150; wherein the pad 150 is provided with an avoidance hole 151 corresponding to the via 101.

[0048] Please continue reading Figure 3 The preparation method in this embodiment further includes step S300, in which liquid is poured into the receiving hole formed by the connecting through hole of the spacer and the via hole of the PCB board and solidified to fill the receiving hole; thereby achieving fixed connection of multiple PCB boards.

[0049] After the welding of multiple PCBs is completed, a sealed channel (accommodating hole 1001) that penetrates multiple PCBs is left at each drilled hole. A thermoplastic or thermosetting, or solidifiable liquid material is injected into the sealed channel. Under certain conditions, the liquid solidifies into a solid, forming a fixing bolt that fastens multiple PCBs together. Optionally, the injected liquid material is plastic or solder, etc. Fig.10 , Fig.10 It is a schematic structural diagram of an embodiment of a PCB board assembly of the present application, wherein the injected liquid forms a fixing bolt 180 after solidification.

[0050] The preparation method of the PCB board assembly provided in the embodiment of the present application realizes the fixed connection of multiple PCB boards by connecting adjacent PCB boards with spacers with holes, and then pouring liquid into the receiving holes and solidifying to fill the receiving holes. The PCB board assembly obtained by the preparation method has the characteristics of compact overall structure, small space occupied by connecting parts and high connection reliability. It can be applied to electronic equipment and is conducive to the miniaturization design of electronic equipment.

[0051] See also Fig.11 , Fig.11 1 is a flow chart of another embodiment of the method for preparing a PCB board assembly of the present application. The preparation method in this embodiment includes but is not limited to the following steps.

[0052] Step S100, forming via holes on at least two PCB boards respectively.

[0053] Step S200, placing a spacer with connecting through holes between adjacent PCB boards and connecting the spacers to the adjacent PCB boards respectively.

[0054] Step S300, pouring liquid into the receiving hole formed by the connecting through hole of the spacer and the via hole of the PCB board, and solidifying the liquid to fill the receiving hole.

[0055] Different from the above-mentioned embodiment, the preparation method in this embodiment further includes step S400, setting a jig or blind scoop at the position corresponding to the via hole of the outermost PCB board, and then forming a plug cap structure at the end after the injected liquid solidifies.

[0056] In order to enhance the reliability of the fixing bolt 180, the bolt cap 181 can also be made by a jig or blind fishing, so that the fixing effect is more significant. Fig.12 and Fig.13 , Fig.12 It is a schematic diagram of the structure of forming a bolt cap by means of a jig, and the number 108 in the figure represents the jig. Fig.13 The schematic diagram is a structure diagram of forming a bolt cap by blind fishing. Specifically, a blind fishing 107 of a certain shape can be directly made on the PCB board, a certain depth can be processed by CNC, and then liquid is injected, and finally solidified into a fixing bolt 180 with a bolt cap 181, which can tightly fix multiple PCBs together. The fixing bolt formed in this way is flush with the PCB board without protrusions.

[0057] Among them, in the solution where the fixing bolt 180 is made of metal tin, it can be carried out simultaneously with the patching of the electronic device. Please refer to Fig.14 and Fig.15 , Fig.14 This is a schematic diagram of the structure before the tin material fixing bolt is formed during the patch process. Fig.15 It is a schematic diagram of the structure after the tin material fixing bolt is formed in the patch process; in this process, a stepped steel mesh can be used to brush a relatively large amount of solder paste 106 above the receiving hole 1001. After passing through the reflow oven, the solder paste 106 melts and flows into the receiving hole 1001 to form a fixing bolt 180. The "rough" inner wall of the channel is firmly combined with the fixing bolt 180, thereby strengthening the bonding force of multiple boards. The mark 105 in the figure is a small solder paste used for patching with the electronic component 104.

[0058] The preparation method in the embodiment of the present application is to firmly fix the combined PCB together by designing fine vias in the structure of the multi-layer combined PCB board and injecting liquid to solidify into a plug. This generated fixing plug replaces the traditional screw fixing form, saves space on the PCB for layout of components and connection of signal lines, and contributes to the miniaturization of the internal equipment.

[0059] In addition, in some other embodiments, the PCB board stacking structure may not be limited to the aforementioned embodiment. Fig.16 and Fig.17 , Fig.16 is a structural schematic diagram of another embodiment of the PCB board assembly of the present application, Fig.17 1 is a structural schematic diagram of another embodiment of the PCB board assembly of the present application, in which 180 is a fixing bolt, 104 is an electronic component, and 110, 120, 130, and 140 are PCB boards respectively. Fig.16 The middle part is the matching connection structure of large and small PCB boards (or raised boards). Fig.17 The figure shows the connection structure of a four-layer (or more-layer) PCB board. The detailed features of this part are within the scope of understanding of those skilled in the art and will not be elaborated here.

[0060] Furthermore, the present application also provides an electronic device. The electronic device in this embodiment may include a mobile phone, a tablet computer, a laptop computer, a wearable device, etc. This embodiment is described by taking a mobile phone as an example. Fig.18 and Fig.19 , Fig.18 is a structural diagram of an embodiment of the electronic device of the present application, Fig.19 yes Fig.18 The electronic device in the embodiment is a schematic cross-sectional view of the structure at AA. The electronic device in the embodiment may include a display module 30, a middle frame 10, a control circuit board 20 and a back cover 40. The control circuit board 20 may be prepared by the preparation method in the above embodiment.

[0061] Optionally, the display screen module 30 and the back cover 40 are respectively matched with the middle frame 10 to form an accommodation space 1000, and the control circuit board 20 is disposed in the accommodation space 1000. The control circuit board 20 is electrically connected to the display screen module 30, and the control circuit board 20 is used to control the display screen module 30. The detailed technical features of the other parts of the electronic device are within the scope of understanding of those skilled in the art and will not be repeated here.

[0062] See also Fig. 20 , Fig. 20It is a schematic diagram of the structural composition block diagram of an embodiment of an electronic device of the present application. The electronic device can be a mobile phone, a tablet computer, a laptop computer, a wearable device, etc. The diagram of this embodiment takes a mobile phone as an example. The structure of the electronic device may include an RF circuit 910, a memory 920, an input unit 930, a display unit 940 (which may be the display screen module 30 in the above embodiment), a sensor 950, an audio circuit 960, a wifi module 970, a processor 980 (which may be the control circuit board 20 in the above embodiment) and a power supply 990, etc. Among them, the RF circuit 910, the memory 920, the input unit 930, the display unit 940, the sensor 950, the audio circuit 960 and the wifi module 970 are respectively connected to the processor 980; the power supply 990 is used to provide power to the entire electronic device.

[0063] Specifically, the RF circuit 910 is used to receive and send signals; the memory 920 is used to store data instruction information; the input unit 930 is used to input information, which may specifically include a touch panel 931 and other input devices 932 such as operation buttons; the display unit 940 may include a display panel 941, etc.; the sensor 950 includes an infrared sensor, a laser sensor, etc., for detecting user approach signals, distance signals, etc.; the speaker 961 and the microphone (or microphone) 962 are connected to the processor 980 through the audio circuit 960 for receiving and sending sound signals; the wifi module 970 is used to receive and transmit wifi signals, and the processor 980 is used to process data information of the electronic device. For the specific structural features of the electronic device, please refer to the relevant description of the above embodiment, which will not be described in detail here.

[0064] The PCB board assembly of the electronic device in this embodiment is connected by using a spacer with holes between adjacent PCB boards, and then liquid is poured into the receiving hole and solidified to fill the receiving hole, thereby achieving fixed connection of multiple PCB boards. The PCB board assembly obtained by this preparation method has the characteristics of compact overall structure, small space occupied by connecting parts and high connection reliability, and can be applied to electronic equipment, which is conducive to the miniaturization design of electronic equipment.

[0065] The above descriptions are only some embodiments of the present application, and do not limit the protection scope of the present application. Any equivalent device or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for preparing a PCB board assembly, characterized in that: The preparation method comprises: Forming via holes on at least two PCB boards respectively; A spacer with connecting through holes is arranged between adjacent PCB boards and connected to the adjacent PCB boards respectively; wherein the connecting through holes of the spacer are arranged corresponding to the via holes on the adjacent PCB boards; Liquid is poured into the receiving hole formed by the connecting through hole of the spacer and the via hole of the PCB board, and the liquid is solidified to fill the receiving hole, thereby achieving fixed connection of multiple PCB boards.

2. The preparation method according to claim 1, characterized in that: In the step of arranging a spacer with connecting through holes between adjacent PCB boards and connecting them respectively to the adjacent PCB boards, the spacer is a metal gasket, which is welded and connected to the pads on the adjacent PCB boards respectively, wherein the pads are provided with avoidance holes corresponding to the through holes.

3. The preparation method according to claim 2, characterized in that: The aperture of the pad avoidance hole is larger than the aperture of the spacer connecting through hole, and the aperture of the spacer connecting through hole is larger than the aperture of the PCB board through hole.

4. The preparation method according to claim 1, characterized in that: In the step of arranging a spacer with connecting through holes between adjacent PCB boards and connecting them to adjacent PCB boards respectively, the spacer is a sealing ring made of elastic material, and the sealing ring is connected to the adjacent PCB boards through external pressure.

5. The preparation method according to claim 4, characterized in that: The sealing ring is made of rubber or elastic resin.

6. The preparation method according to claim 1, characterized in that: In the step of arranging a spacer with connecting through holes between adjacent PCB boards and connecting them respectively to the adjacent PCB boards, the spacer is a solder material connected between the pads of adjacent PCB boards; wherein the pads are provided with avoidance holes corresponding to the through holes.

7. The preparation method according to claim 1, characterized in that: In the step of pouring liquid into the receiving hole formed by the connecting through hole of the spacer and the via hole of the PCB board and solidifying the liquid to fill the receiving hole, the material of the liquid is plastic or solder.

8. The preparation method according to claim 1, characterized in that: The preparation method also includes: setting a jig or blind scoop at the position corresponding to the via hole of the outermost PCB board, so that in the step of pouring liquid into the receiving hole formed by the connecting through hole of the spacer and the via hole of the PCB board and solidifying to fill the receiving hole, the poured liquid forms a plug cap structure at the end after solidification.

9. A PCB board assembly, characterized in that: The PCB board assembly is prepared by the preparation method described in any one of claims 1 to 8.

10. An electronic device, characterized in that: The electronic device comprises the PCB board assembly according to claim 9.

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